The present invention relates generally to thin film techniques. More particularly, the present invention provides a system and a method for processing thin-film photovoltaic devices based on copper indium diselenide species (CIS), copper indium gallium diselenide species (CIGS), and/or others. The invention can be applied to thin film photovoltaic devices in panel modules, flexible sheets, building or window glass, automotive, and others.
In the process of manufacturing CIS and/or CIGS types of thin films, there are various manufacturing challenges, such as performing large scale thermal reactive treatment in a gaseous environment, maintaining structure integrity of substrate materials with extra large form factors, ensuring uniformity and granularity of the thin film material, etc. While conventional techniques in the past have addressed some of these issues, they are often inadequate in various situations. For example, a process of forming the gaseous environment for the reactive treatment includes supplying a work gas comprising gaseous selenide species into a furnace. The selenide species as a work gas not only is a relative expensive ingredient for the thin-film material but also is a potential hazard of environment. Therefore, it is desirable to have improved system and method for properly handling the work gas for large scale manufacture of thin film photovoltaic devices with substantial cost saving and environmental benefit.